Synthesis of EnantiopureN-tert-Butoxycarbonyl-2-aminocycloalkanones

Abstract
A route to enantiomerically pure N-tert-butoxycarbonyl-2-aminocycloalkanones (ring size: 5-8 membered) from the corresponding cycloalkene oxides is described. The procedure involves (1) aminolysis with (S)-α-methylbenzylamine/Me3A1 and chromatographic separation of diastereomers, (2) hydrogenolysis to afford the trans-2-aminocycloalkanols, (3) tert-butoxycarbonyl (Boc) protection, and (4) PCC oxidation.